I have successfully installed OSR and created WLS Domain using config.cmd. But when I try to start by command line (startManagedWebLogic.cmd osr_server1) I got the error "server is unknown". I have no idea what could be wrong.

Basically I followed http://niallcblogs.blogspot.com.br/2010/09/oracle-service-registry-and-osb11g.html.
The complete command line is:

weblogic.management.ManagementException: The server name osr_server1 is unknown
to the administration server. Check if restart is required.
at weblogic.management.provider.internal.RuntimeAccessImpl.initialize(Ru
ntimeAccessImpl.java:447)
at weblogic.management.provider.internal.RuntimeAccessService.start(Runt
imeAccessService.java:49)
at weblogic.t3.srvr.ServerServicesManager.startService(ServerServicesMan
ager.java:461)
at weblogic.t3.srvr.ServerServicesManager.startInStandbyState(ServerServ
icesManager.java:166)
at weblogic.t3.srvr.T3Srvr.initializeStandby(T3Srvr.java:881)
at weblogic.t3.srvr.T3Srvr.startup(T3Srvr.java:568)
at weblogic.t3.srvr.T3Srvr.run(T3Srvr.java:469)
at weblogic.Server.main(Server.java:71)

Yes, there are the tags you have suggested. The complete config.xml is below.
I tried:
C:\Oracle\Middleware\user_projects\domains\base_domain\bin>startManagedWebLogic.
cmd osr_server1
When asked the user, I tried the node-manager-username weblogic_osr2 and the admin user but I always received the error: The server name osr_server1 is unknown to the administration server.

it seems alright.
Login to adminConsole and see if everything ok in the Servers page.
Try assigning a machine name to it.
Check if your logged in the right machine.
Bring up the node managers and try to start it from adminconsole.